Corylin accelerated wound healing through SIRT1 and PI3K/AKT signaling: a candidate remedy for chronic non-healing wounds

Neutrophil extracellular traps with low concentrations induce proliferation and migration of human fibroblasts via activating CCDC25/ILK/PI3K/AKT pathway

Neutrophil plays an important role in the early stage of wound healing. Excessive neutrophil extracellular traps (NETs) which are produced by neutrophil have been proved as a significant unfavorable factor for wound healing by impairing the function of human skin fibroblasts. However, the effect of NETs with low concentrations on fibroblasts remains unclear. The interaction between CCDC25 and ILK in fibroblast were found to be activated by NET-DNA with low concentrations. Additionally, phosphorylation of PI3K and AKT was increased in NET-stimulated fibroblasts but was inhibited by CCDC25 knockout or ILK knockdown. NETs-induces proliferation and migration ability of fibroblast were also reduced by application of CCDC25 sgRNAs or ILK shRNAs. This study demonstrates that low concentrations of NETs, upon biding with CCDC25, activates the ILK/PI3K/AKT signaling pathway in skin fibroblasts, leading to increased cell proliferation and migration activity.

Photobiomodulation effects on fibroblasts and keratinocytes after ionizing radiation and bacterial stimulus

OBJECTIVE

Photobiomodulation therapy (PBMT) has proven to reduce inflammation and pain and increase wound healing. Thus, the aim of this study was to analyze the effects of PBMT parameters on migration, proliferation, and gene expression after ionizing radiation and bacterial-induced stress in an in vitro study.

DESIGN

Keratinocytes (HaCaT) and Fibroblasts (HGFs) were grown in DMEM with 10 % fetal bovine serum until stressful condition induction with lipopolysaccharide (LPS) of Escherichia coli (1 µg/mL), Porphyromonas gingivalis protein extract (5 µg/mL) and ionizing radiation (8 Gy). Low-laser irradiation (660 nm, 30 mW) was carried out in four sessions, with 6 h intervals, and energy density of 2, 3, 4, and 5 J/cm². Scratch assays, immunofluorescence, and RT-qPCR were performed.

RESULTS

Treated fibroblasts and keratinocytes showed significant response in proliferation and migration after scratch assays (p < 0.05). Higher expressions of α-SMA in fibroblasts and F-actin in keratinocytes were observed in cells subjected to 3 J/cm². PI3K-pathway genes expression tended to enhance in fibroblasts, presenting a higher relative expression when compared to keratinocytes. In keratinocytes, PBMT groups demonstrated deregulated expression for all inflammatory cytokines' genes tested while fibroblasts presented a tendency to enhance those genes expression in a dose dependent way.

CONCLUSIONS

The present study showed that delivering 660 nm, 30 mW was effective to stimulate cell migration, proliferation and to accelerate wound healing. PBMT can modulate cytokines and pathways involved in wound repair. The different energy densities delivering distinct responses in vitro highlights that understanding laser parameters is fundamental to improve treatment strategies.